Whereas you would probably think that Night Lords are the best Chaos Legion to make use of the Raptor Talon formation, I actually think that the Black Legion Speartip detachment may be one of the best ways to field this particular formation. First of all, let’s look at the Black Legion and Speartip detachment special rules:
—Black Legion Faction—
 All Black Legion units that have access to it get VotLW for free. If they have this rule, then they also get Hatred against everyone and, if they are fighting against any Imperium armies, they get to re-roll ALL to Hits against them (i.e. not just the first round of combat).
 Abbadon is the only Unique character that a Black Legion formation/detachment can take but, unlike other “undivided” Traitor Legions, Black Legion units/characters can choose to upgrade to any Mark they want.
—BL Speartip Detachment—
 All non-vehicle members of this detachment get free Fear and Crusader USRs
 Any units from this detachment that have Deep Strike may attempt to come in from Reserves starting turn 1, and your WL and his unit may choose to automatically come in from reserves on turn 1.
Now, combine all these rules with the Raptor Talon (Jump Pack Chaos Lord, 3-5 units of Raptors and/or Warp Talons) itself, which provides the following benefits:
 Units from this formation can charge on the same turn they arrive from DS Reserve, but count as having made a Disordered Charge if they do so
 If two or more units from a Raptor Talon charge an enemy unit, that enemy unit has -2Ld until the end of the turn.
Finally, since Black Legion units can take any Mark they want, you can “upgrade” your Lord/squads to maximize a specific role in this “kick in the door” style formation. Taking all of these synergistic rules together, I think you can make a very potent battle group that looks something like this:
 Chaos Lord with JP, Mark of Nurgle, Sigil of Corruption, PF/LC, and Skull of Ker’ngar (Relic)
 Three squads of 10 Raptors, all with Mark of Slaanesh, Icon of Excess, 2 MGs, and PF/LC on the Champion
 One squad of 10 Warp Talons with Mark of Nurgle (Jump Lord attaches to them)
So, once you combine all the “cascading” bonuses, each of these squads gets Hatred (or re-rolls every round against Imperium units), gets Crusader/Fear, gets a chance to arrive by Deep Strike on turn 1 and still charge that same turn (the Jump Lord and Warp Talons will arrive automatically turn 1, if you need them to), and can inflict -2Ld on enemy units while getting “free” Ld10 (from VotLW) on themselves. The Raptor squads also can hit their target with 2 MGs each before charging, strike at I5 (so likely before most opponents), and get FNP as long as the Icon bearer is still alive.
As for the Jump Lord and Warp Talons, they are Fearless (thanks to the Lord), can potentially Blind nearby enemies (thanks to the Warp Talon “Warpflame Strike” rule), and are all T5 to better absorb enemy Overwatch/attacks in CC. The Lord himself has a 3+/4++ and can either use his PF or his I5 LC with 4A base which, combined with the 20 x S4 AP3 Shred attacks from the Warp Talons on their Deep Strike charge, ought to deal with almost any MEQ or below that doesn’t have a 2+ armor save.
Now, you obviously don’t want to target enemy uber close combat units with this task force since, while they hit pretty hard, compared to things like Hammernators, Wulfen, Necron Wraiths, Meganobz, Genestealer Cult Purestrain Genestealers, etc., etc., they are relatively fragile and will get clobbered by dedicated assault units.
What I think this battle group can excel at is, number one, as the ultimate “bully” unit for turn 1 assaults (and hopefully Sweeping Advances, with the help of the Crusader USR) against weak “shooty” opponents (Tau, Eldar, and Astra Militarum all come immediately to mind) and, number two, very capable “tar pit” units for very dangerous opponents that you don’t want shooting and/or assaulting the rest of your army. With the ability to reliably charge on Turn 1, you can “suppress” dangerous threats like Stormsurges, Wraithknights, Imperial Knights, Devastator Centurions, Astra Militarum “Blob” Squads, Tau Pathfinders, Eldar Jetbikes, Loota Boyz, TFCs, etc. etc. before they can every really get into action by tying them up in close combat right away: if you are lucky, you might even kill them off, but at the very worst you keep them from moving, shooting, and/or assaulting for several turns, thereby allowing the rest of your army to operate without danger from them.